26 Mr. E. H. Griffiths and Miss Marshall on the 



18. Explanation of the Tables. 



Tables lettered A give the experimental data ; the deductions 

 from those data are given in Tables lettered B. 



(We have arranged the experiments in order of temperature 

 rather than historical order, as consecutive experiments were 

 not always at the same temperatures.) 



Tables A. 



Col. I. a and b give the number and date of the experi- 



ment. 



„ II. a and b give the number of Clark cells in series, 



and the number of the dropper used. 



„ III. Gives the mass of benzene evaporated, after cor- 

 rection to vacuo (M). 



„ IV. The time during which the current was main- 

 tained (£ K ). 



„ V. The time from commencement to end of experi- 



ment (£ g ), i. e. y the time during which the 

 " stirring supply " has to be estimated. 



„ VI. The number of revolutions per second (r ± ) of the 

 stirrer. 



„ VII. The difference between the initial (0 O ') and the 

 final temperature (0 O ") of the surrounding- 

 walls. 



„ VIII. Let 0i (initial calorimeter temperature) exceed 

 0q by d', and let 0/' (final calorimeter tem- 

 perature) exceed o f/ by d" ; then this column 

 gives the value of d' — d" . Hence 

 {(0o'-0o")-(d'-d")} 

 gives the difference between the initial and 

 final temperature of the calorimeter. 



„ IX. The capacity for heat of the calorimeter and its 

 contents at the mean temperature of the tank 



„ X. The temperature of the Clark cells. 



„ XI. The value of R J<? , L e., the resistance of the 

 calorimeter-coil at temperature ly when the 

 potential-difference of its end is ne. (From 

 Table III. p. 17.) 



